Slub catcher



March 22, 1960 s. L. ABBOTT 2,929,129

SLUB CATCHER Filed Dec. 15, 1958 3 Sheets-Sheet l March 22, 1960 s. L. ABBOTT SLUB CATCHER 5 Sheets-Sheet 2 Filed Dec. 15. 1958 March 22, 1960 s. L. ABBOTT 2,929,129

SLUB CATCHER Filed Dec. 15, 1958 3 Sheets-Sheet 3 SLUB CATQ'JHER Samuel L. Abbott, Wilton, N.H., assignor to Abbott Machine (30., lnc., Wilton, N.H., a corporation of New Hampshire Application December 15, 1958, Serial No. 780,456 2 Claims- (Cl. 28-64) My United States Patent No. 2,625,732, dated January 20, 1953 discloses a slub catcher in which an enlargement in the yarn is laterally deflected by the inclined entering edge of an upper blade which defines a passage for normal yarn, and the yarn led by such deflection into a slot defined-by a lower blade, with the yarn passage defined by the upper blade being provided with an enlarged exit for the release of knots or very short enlargements which do not engage the lower blade as the yarn is deflected, and with the slot defined by the second blade continuing laterally beyond the path of yarn deflected to this exit for knots to a region where a slub is snagged, as by a tapered snagging slit.

The ideas underlying such a device are, first, that normal yarn will not be deflected by the first or upper blade but will run freely past it, second, that if it is simply a knot that is deflected by the first or upper blade, the normal yarn that then enters the slot defined by the second or lower blade will run freely through this slot and the yarn will return to its normal path as soon as the knot has escaped through the knot exit, and third, that when a slub is deflected into this slot defined by the second blade it cannot escape because this slot has no exit corresponding to the exit by which a knot leaves the first blade, so that the slub will continue to be deflected until snagged.

Further study has convinced me that it is necessary to consider lengthwise movement of a slub while it is being deflected. Long, soft slubs present a ditficulty. It is po'ssible for such a device to catch the long, soft slubs, but in practice the long, soft slubs cannot all be caught unless the passage for the yarn is so restricted as to cause some of the ordinary larger-diameter portions of the yarn to be caught also. The long, soft slub is apparently easily compressed to about the actual size of the frequently occurring larger-diameter parts of the yarn. It appears that in most cases the long, soft slub, while being deflected, is also moving lengthwise through the device and that those slubs that have escaped have been able to work their way lengthwise out of the device before 2,929,129 Patented M r. 22, 1960 of the larger-diameter portions of the normal yarn. This is undesirable because it results in additional knots.

Considering the situation where with a .808 inch setting perhaps 25 percent of the slubs escape, it will be seen that what is needed is a means of increasing selectivity sufliciently to catch all of the slubs without necessarily decreasing the setting to a point that will catch the largerdiameter portions of the normal yarn.

It is accordingly the principal object of this invention to increase selectivity as between slubs and larger portions of acceptable yarn.

In this type of device in which an enlargement in the yarn is deflected laterally by a slanting blade, the yarn may be compared to a bow string. The yarn normally runs straight vertically under the influence of its tension alone. To deflect the yarn from this path, to which it is urged by its own tension, force must .be applied by the blade, and this force is secured by the reaction of the blade o'n the running yarn. If a theoretical balanced condition is assumed in which the yarn were to continue running in a constant deflected path, neither moving up or down the blade away from or toward the undeflected vertical position, it may be shown graphically that the force of the blade reacting on the yarn is very nearly pro-- portional to the extent of the deflection from the normal vertical path. p

In observing settings which are not close enough to catch any of the slubs, for instance a .009 inch setting with the above 40s yarn, the yarn may be seen to vibrate, but evidently not far enough, at any one time, to be snagged. From this it may be concluded that with these slightly too wide settings, the blades did not apply enough deflecting force, particularly where the yarn was considerably deflected in a bow string condition but needed to be still farther deflected in order to be snagged.

In the device of my said patent, assuming a slub is deflecting along the upper and lower blades toward the snagging slit, and is simultaneously moving lengthwise of itself through these blades, it may be presumed that both blades are compressing the slub, resisting its lengthwise travel and reacting upon the slub to urge it to a still more deflected condition. The yarn tension is of course resisting this deflection.

I have discovered that the device of my said patent has a previously unappreciated defect, this defect being as follows. When the slub reaches the exit of the upper blade there ceases to be a joint or double action of the reaches the snagging slit and is snagged there seems to depend upon its rate of lateral deflection relative to its rate of lengthwise. travel.

The slub could be deflected faster and more positively laterally by setting the opposed elements of the slub catcher closer together so that the blades exerted a greater deflecting force, but this tends to deflect the normal larger-diameter parts of the yarn as well as the slubs.

It may be noted that in worsted 40s yarn having an average diameter of approximately .007 inch there will be places having diameters of as much as .009 inch. Using a setting of .008 inch for the earlier slub catcher it is possible to catch perhaps 75 percent of the slubs in this yarn without catching any of the normal largerdiameter portions of the yarn. Decreasing the setting to ,007 inch catches all of the slubs but also catches some upper and lower blades upon the slub. The deflecting action is then only that of the lower blade, whereas the tension forces opposing deflection are nearing their maxslubs from devices using the principle of my patent has been due to this defect which can be remedied ho'wever as herein explained.

As will be seen from the accompanying drawings and following detailed description, in the preferred form of the invention, at about the degree of deflection of the yarn which corresponds to its reaching the exit of the upper or first blade, but before the region of maximum lateral displacement of the slub, the slub encounters a new third or lowermost blade which, soto speak, takes over the escape-resisting and laterally-deflecting functions relinquished by the upper blade. In this way the slub is led to its maximum lateral displacement, where it is snagged, while under the escape-resisting and laterallydeflecting influence of both the second and the new third blade.

In the accompanying drawings: Fig.1 is a view mainly. in front elevation showing the front cover plate of a traveling spindle winding unit with parts removed and showing the improved slub catcher of the present invention applied thereto;

Fig. 2 is a vertical sectional view taken on the line 22 of Fig. l;

Fig. 3 is a diagram in the nature of a left-side elevation of the two blocks of the slub catcher, to greatly enlarged scale, and showing various positions of the yarn and the relation of the yarn to the blades;

Fig. 4 is a face view of the opposed portions of the pivotally mounted block and the stationary block;

Fig. 5 is an elevation of the right side or operative face of the pivotally mounted block;

Fig. 6 is a plan of the block of Fig. 5; and

Fig. 7 is a perspective view of the stationary block.

In the preferred form of slub catcher illustrated, the yarn Y runs as in Fig. 1 between a stationary block 10, which is cut away on its left face, as subsequently described, to form the three blades mentioned above, and a pivotally mounted block 11, which is cut away on its right face to receive the yarn. Fig. 1 exaggerates this cutting away of the block 11.

As shown in Fig. 2, the front cover plate 15 of a winding unit carries a base black 16. The stationary block is secured in an inclined position to a corresponding in- .clined surface of the base block 16. The pivotally mounted block 11, Fig. l, is rotatable by a spindle 18, having a pivot portion which passes through the movable block and pivots in the base block as indicated at 19 in Fig. 2.

The spindle 18 is yieldingly urged against the movable 'the two blocks for cleaning as by an air blast.

The usual yarn guides 23 and 24, above and below the slub catcher, guide the yarn in a vertical path in its upward travel from a supply to the winding package and a usual tension device 25 applies the desired tension.

The deflecting action of the slub catcher upon the yarn is to the left in Fig. 2 and away from the observer in Fig. l. A guide bracket 27 engages the yarn below the slub catcher and is adjustable vertically to vary the length of yarn that can be deflected, that is, the length of the bow-string, thus to vary the sensitivity of the slub catcher.

The pivotally mounted block 11 best shown in Figs. 5 and 6 is cut away by grinding on its face which opposes the block 10 to receive the yarn, the extent of this cutting away, dimension A, being exaggerated irtFig. 6. An inclined surface portion B of the block 11 defines tapered snagging slits in conjunction with blade surfaces of the block 10.

It may be mentioned that, for converting the device to handle various yarn numbers, removable blocks 11 are provided in a range of dimensions A, the setting of the slub catcher (.008 inch, .012 inch, etc.) being determined by this dimension A of the removable block, and the dimensions and form of the companion stationary block it) being constant.

The stationary block 10, shown in perspective in Fig. 7, is essentially rectangular with various cut away surfaces.

Two V-shaped slots divide the operative face of the block into first, second and third blades 31, 32 and 33, the elfective faces of which preferably lie in the same vertical plane.

Up to the level of the-base of the upper blade 31, the

, 4 I block is chamfered, the chamfered surface being indicated at 34, this chamfer reducing the length of the faces of blades 32 and 33 to the le 'jngth C. The portion of this chamfered surface 34 adjacent to the faces of blades 32 and 33 provides an easy entrance for the yarn or slub into the slots or passages defined by the blades and the block 11. The upper blade 31 is cut away by removal of the material shown in broken lines in Fig. 7 to form a rectangular exit 35 for the release of knots or short enlar'gements which are not engaged by the second blade 32. In Fig. 3, the blocks 10 and 11 are shown together in operative position with the block 10 and its blades 31, 32 and 33 behind the block 11. Only the operative face portions of the blades are shown. Three positions of the yarn are shown. Position N represents the normal running position in which the yarn runs between the upper blade 31 and block 10 out of reach of the blades 32 and 33. Position KS indicates the bow string condition of the yarn when the yarn is deflected to the exit 35 of the upper blade and the upper blade becomes ineffective to 'prevent escape of an enlargement or to deflect it farther.

This deflection to this position KS can be caused either by a knot or by a slub. If the deflection to position K--S is caused by a knot and no slub is involved, the knot will escape at this position and the yarn will snap back to position N. If this deflection to position KS is caused by a slub, the deflection will continue to a position such as indicated at S where the slub is caught in the tapered slots formed by blades 32, 33 and the inclined surface portion B of block 11.

It will be seen that although the escape-resisting and defleeting actions of the blade 31 have ended at the opening 35, these functions of the blade are taken over by the lowermost blade 33 and the slub is led to its maximum displacement while under the escape-resisting and deflecting influence of both the second and third blades.

The result of the improved action is that the slub catcher is capable of more selective action as between long, soft slubs and the normally occurring large diameter portions of the yarn. Thus it is not necessary, in order to catch substantially all the long, soft slubs, to employ such a close setting as will catch the unobjectionable larger diameter portions of the yarn.

The change from two blades of the prior device to three blades in the present device yields a disproportionate increase in action on the slub in that the new third blade acts to prevent a slub from escaping and to cause it to continue its deflection while in the critical travel from the path indicated at K-S to position S, during which time the bow string of yarn is most widely extended, the tension required to extend it is at a maximum, but blade 31 has ceased to act. This result could not be obtained practically by merely narrowing the gap defined by the lower blade of the prior device, giving it a stronger action, because this would tend to deflect somewhat enlarged normal "yarn which reached the lower blade of the prior device,

thus making the device less selective.

The effect of increasing resistance to escape of slubs might be obtained in part by widening the face of the lower blade of the prior device, but since this would at the same time retard deflection in the critical zone, this expedient appears to be no solution to the problem of increasing I selectivity.

I claim:

1. A slub catcher including means for defining a passage through which normal yarn is adapted to run, said passage-defining means including a blade having its entering side inclined to the path of the yarn so as to tend to deflect enlarged yarn laterally and said passage having an enlarged exit opening laterally displaced from the normal yarn path for the release of knots or short yarn enlargements deflected to said exit opening, a second blade spaced in advance of the first blade, said second blade having its entering side inclined to the path of the yarn and extending laterally beyond the path of the deflected yarn runm'ng to said exit opening, and a third blade spaced from the second blade in advance thereof in a region which begins before the region of maximum lateral displacement of a slub beyond the exit and extends into said region of maximum lateral displacement, said third blade also having its entering side inclined to the path of the yarn, the slub catcher including surface portions cooperating with the second and third blades to press a deflected slub against said second and third blades whereby the slub is led into said region of maximum lateral displacement 10 6 while under the deflecting and escape-resisting influence of both the second and third blades, the slub catcher including means for snagging the slub in said region of maximum lateral displacement.

2. A slub catcher as claimed in claim 1 in which the third blade extends to said region of maximum lateral displacement from approximately as near the normal yarn path as the path of yarn running to the exit opening.

No references cited. 

